Re: Utf8 to Utf32 cast cost

[Kagamin via Digitalmars-d-learn]

On Monday, 8 June 2015 at 10:59:45 UTC, Daniel Kozák wrote:
import std.conv;
import std.utf;
import std.datetime;
import std.stdio;
void f0() {
    string somestr = "some not so long utf8 string 
forbenchmarking";
    dstring str = to!dstring(somestr);
}


void f1() {
    string somestr = "some not so long utf8 string 
forbenchmarking";
    dstring str = toUTF32(somestr);
}

void main() {
    auto r = benchmark!(f0,f1)(1_000_000);
    auto f0Result = to!Duration(r[0]);
    auto f1Result = to!Duration(r[1]);
    writeln("f0 time: ",f0Result);
    writeln("f1 time: ",f1Result);
}


/// output ///
f0 time: 2 secs, 281 ms, 933 μs, and 8 hnsecs
f1 time: 600 ms, 979 μs, and 8 hnsecs

Chances are you're benchmarking the GC. Try 
benchmark!(f0,f1,f0,f1,f0,f1);